Diamond type tooth for rotary stone cutting saws



ff ffy March 18, 1952 DIAMOND TYPE TOOTH FOR ROTARY STONE CUTTING SAWS V. J. FANTOZZI ETA Filed April 13, 1949 Zea/@old Patented Mar. 18, 1952 DIAMOND TYPE TOOTH FOR ROTARY `STONE CUTTING SAWS Vincent J. Fantozzi and Leopold H. Metzger, ChicagoJ Ill., assignors to Super-Cut, Inc., Chicago, Ill., a corporation of Illinois Application April 13, 1949, Serial No. 87,264

Claims. 1

The present invention relates generally to teeth for use as parts of saws. More particularly the invention relates to that type of tooth which is adapted, with like or similar teeth, to be arranged in an annular series around the outer margin of a disc-lile blade, forms with the other teeth and the blade a rotary saw for cutting stone, such, for example, as limestone, marble and granite and comprises a dat rectangular body which is formed of suitable metal, fits within a rectangular notch in the outer margin of the disc-like blade, embodies coacting groove and rib connections at its front and rear side margins for holding it against lateral displacement while at the same time permitting it to be removed by outward sliding movement, and has at itslouter end a cutting part which is bonded in place and consists of a metallic matrix with diamonds therein.

In using a rotary stone cutting saw the stone and saw are moved relatively to one another and a liquid coolant is discharged so as to effect cooling and cleaning of the teeth as they pass successively through the stone. In practice it has been found that prior art saw teeth are subject to certain objections and require frequent replacement. li the iirst place the impact and pressure to which the leading ends of the cutting parts of the teeth are subjected is sometimes so great that it breaks the bond between the cutting parts and the teeth bodies with the result that the cutting parts become dislodged and sometimes in connection with outward fiinging by centrifugal force cause material damage or injury. Secondly, the leading ends of the cutting parts, because they are exposed, are subjected to theabrading action of the sludge consisting of the out stone particles and the liquid coolant and hence quickly become undercut or worn away so far as their front and side portions are concerned.

Gne object of the invention is to provide a diamond saw tooth which is an improvement upon, and obviates the objections to, standard or conventional teeth and is characterized by materially longer life and better, smoother and quieter operation. Generally speaking, the improved tooth embodies at the outer corners of its body outwardly extending, spaced apart metallic lugs which denne with the outer margin of the body a U-shaped frame or socket-like seat in which is mounted the cutting part consisting of themetallic matrix with crushed or fragmented diamond distributed throughout. The leading lug, i. e., the lug on the iront outer corner of the `body has a twofold purpose in that it knot only lserves to absorb the shock which is normally transmitted to the leading end of the cutting part and tends to dislodge such part from its bonded relation with the outer end of the body, but also forms va barrier for protecting the leading end ,of the cutting part from the abrading action of the sludge, thereby preventing undercutting or rapid wearing away of the front and side portions oi the leading end of the cutting part. The trailing lug, i. e., the lug on the rear outer corner of the body, coacts with the iront lug positively to lock or hold the cutting part in place and also assists in resisting impact and pressure on the cutting part.

Another object of the invention is to provide a diamond type saw tooth in which the outwardly extending lugs on the body are formed of such metal that when the tooth is used in connection with the cutting of a particular type of stone the rate of wear of the lugs is approximately the same as that of the crushed or fragmented diamonds in the cutting part. In this connection it is to be understood that soft stone, like sandstone, has a greater abrading action than hard stone, such as granite. This invention contemplates when the tooth is used to out comparatively soft stone, forming the lugs mof any hard wear resistant metal, such as steel, and when the tooth is used to out hard stone forming the lugs of softer, less wear resistant metal, such, for example as, red bronze.4 By forming the lugs of the proper metal for a particuular type of stone it is possible so to correlate the rate of wear of the lugs with the rate of wear of the diamonds that the lugs and cutting part wear uniformly. By having vthe lugs and cutting part wear uniformly in connection with cutting of stone of a particular type the tooth lasts longer and cuts more efciently. It is here contemplated that the correlation of the rate of wear of the lugs and the rate of wear of the cutting part means that the lugs will wear away correspondingly to the cutting part to the end that the outer and side portions of the cutting part are always exposed for purposes of cutting.

Another object of the invention is to provide a saw tooth of the type and character under consideration in which the matrix of the cutting part is formed of sintered metal powder, the cutting part after application of solder to the inner side surfaces of the lugs and the outer end surface of the body is molded in place with respect to the body while the .metallic particles are subjected to a sintering temperature and proper pressure, and the aforementioned surfaces are transversely notched in order to increase the area of the solder variety bond between the cutting part and such surfaces.

A further object of the invention is to provide a saw tooth of the last mentioned character in which the upper portion of the cutting part projects outwards of the outer ends of the lugs, and the side portions of the cutting part project outwards of the sides of the lugs and have end eX- tensions in lapped and bonded relation with the sides of the lugs.

A still further object of the invention is to provide a saw tooth which is generally of new and improved construction and not only possesses long life and high wear characteristics, but also is capable of being produced at a comparatively low cost.

Other objects of the invention and the various advantages and characteristics of the present diamond type saw tooth will be apparent from a consideration of the following detailed description.

The invention consists in the several novel features which are hereinafter set forth and are more particularly defined by claims at the conclusion hereof.

In the drawing which accompanies and forms a part of this specification or disclosure and in which like numerals of reference denote corresponding parts throughout the several views:

Figure 1 is a fragmentary side elevation of a rotary stone cutting saw having applied to the outer margin of the disc-like blade thereof a tooth embodying the invention;

Figure 2 is a perspective of the tooth;

Figure 3 is an end view;

Figure 4 is a vertical longitudinal section illustrating in detail the construction and design of the outwardly extending lugs on the outer corners of the body of the tooth and showing the manner in which the cutting part is interlocked with, and bonded to, the inner side surfaces of the lugs and the outer end surface of the body;

Figure 5 is a perspective of the lug equipped body before formation thereon of the cutting part consisting of the metallic matrix with crushed or fragmented diamonds distributed throughout; and

Figure 6 is a section taken on the line 6 6 of Figure 1 and illustrating the manner in which the tooth is slidably connected to the saw blade by coacting or intertting groove and rib connections at its front and rear side margins of the body.

The tooth which is shown in the drawing constitutes the preferred form or embodiment of the invention. It is designated generally by the reference numeral 1 and is adapted in connection with like or similar teeth and a disc-like blade 8 to form a rotary saw for cutting stone. As shown in Figure 1, the blade 8 has in its outer margin an annular series of equidistantly spaced, substantially rectangular notches 9 in which the teeth are mounted. The portions of the outer margin of the blade that define the sides of the notches 9 are double bevelled in order to form inwardly extending ribs I0 of V-shaped cross section. The tooth 1 consists of a body I I and an outer cutting part I2.

The body II of the tooth I is formed of metal. It is shaped conformably to, and fits within, its particular notch 9 in the outer margin of the disc-like blade of the saw. As shown in the drawing the body of the tooth is no greater in thickness than the blade and is arranged in transversely centered relation with respect to the sides of the blade. At its front outer corner the body I I is provided with an integral outwardly extending leading lug I3 and at its rear outer corner the body is provided with an integral outwardly extending trailing lug I4. These two lugs are the same in length and form with the outer end or margin of the body II a U-shaped frame or socket-like seat in which the cutting part I2 of the tooth I is mounted, as described hereafter. The sides of the frame forming lugs I3 and I4 and the sides of the body are preferably but not necessarily flush or coplanar. When the tooth 'I is in its operative position within its particular notch in the outer margin of the disc-like blade of the saw the lugs I3 and I4, as shown in Figure 1, project beyond the periphery of the blade. The front and rear side margins of the tooth body Il have formed therein longitudinally extending grooves I5 of V-shaped cross section. These grooves are shaped to receive and interlock with the ribs I0 and permit the tooth I to be slid longitudinally into and out of its particular notch 9. The lugs I3 and I4 have continuations of the grooves I5 in order to facilitate machine forming of the grooves. The body II of the tooth 'I is removably secured in place by a key type rivet I6. The latter extends through a circular hole I1, half of which is formed in the central portion of the rear side margin of the tooth body and the other half of which is formed in the adjacent portion of the outer margin of the saw blade 8. The inner surfaces of the lugs I3 and I4 and the outer end surface of the body II have transversely extending notches I8 and these are for a purpose to be described more in detail hereafter. Preferably the notches I8 are formed in the aforementioned surfaces by a suitable saw. As best shown in Figure 4 of the drawing, one of the notches in the outer end surface of the body I I is larger than the other notches. It is designated by the reference numeral I9 and is of dovetail configuration to the end that it has a restricted entrance. All of the notches are open ended.

The cutting part I2 of the tooth 'I ts for the most part within, and is bonded by a solder coating 2U to, the U-shaped frame that is formed by the lugs I3 and I4 and the outer end margin of the tooth body II. It consists of a metallic matrix and crushed or fragmented diamonds distributed substantially throughout the matrix. The matrix is molded into place by the use of a suitable properly shaped mold (not shown) and consists of sintered metal powder. In practice it has been found that satisfactory results are obtained when the matrix for the crushed or fragmented diamonds is formed by mixing together and then sintering in connection with the molding operation, iron, copper, tin and nickel. The percentages by weight are iron 26, copper '26, tin 24 and nickel 24. As shown in Figures 2 and 3, the cutting part I2 is thicker than the body I I and hence the sides of the cutting part project outwards of the sides of the tooth body. The outer portion of the cutting `part projects a small distance beyond the outer ends of the lugs I3 and I4. The ends of the sides of the cutting part I2 are extended so as to lap and cover the side surfaces of the lugs. The end extensions of the sides of the cutting part are bonded to the side surfaces of the lugs I3 and I4 by a coating of solder. Preferably the solder which is used for bonding in place the cutting part I2 is a silver solder which is known commercially as Easy-Flow #3. The lower or innermost portions of the sides of the cutting part are downwardly extended into lapped relation with the outer end portions of `the sides of the tooth body II. They are -bevelled, as clearly shown in Figures 2 and 3, and are bonded lin place by a silver solder coating or nlm. `The diamond particles are intimately mixed with the metal powder before molding and sin-tering of the matrix and may extend throughout the entire cutting part or throughout 4substantially all portions with the exception of the bevel-led lower side portions which lap and are bonded to the outer end portions of the sides of the body. In forming Athe tooth 7 the aforementioned silver solder is applied to the proper surfaces of `the lugs I3 and I4 and the body I I. Thereafter the lug equipped body is inserted into a mold having a' cavity which is shaped like the cutting part I2. After insertion of the ybody into the mold the cavity is iilled ,with the matrix forming metal powder having the crushed diamonds or diamond particles intermixed therewith. Thereafter the charged mold is subjected to such heat and pressure as to cause melting of the solder and sintering of the metallic powder. Upon cooling of the tooth the .cutting part I2 is rigid and in firm bonded relation with the body. In connection with formation of the cutting part parts of the diamond impregnated matrix Vforming material flovv into the notches It. After the sintering operation s-uch parts become interlocked with the notches and thus connect the cutting part to the lugs I3 and I4 and the body II. The part ofthe matrix forming material that flows into the enlarged restricted entrance notch I 9 lforms a positive rinterlocking connection between the cutting part and the outer end of the tooth body.

The mesh size of the crushed or fragmented diamonds which extend substantially throughout the metallic matrix of the cutting part is determined by the type of stone which is to be cut by .the tooth. Ii the stone is comparatively soft, like sandstone, diamond particles having a mesh `size 0f from 8 to 40 may 'be employed. If the stone to be cutis marble, diamonds having a mesh size of lfrom to l80 may be employed. If the stone to be cutis extremely hard, like granite, for example. diamonds having `a mesh size of from 40 to 120 maybe used.

The leading lug I3 on the front outer corner of the tooth body I I, in addition to forming with the trailing lug I4 and the outer end of the tooth .v

body a U-shaped frame or rocket-like seat for the cutting part I2, has a twofold purpose. In the first place it serves in connection with a stone cutting operation to absorb the shock which is normally transmitted to the leading end of the cutting part I2 and tends to dislodge such part from bonded relation with the outer end of" 'cutting part I2 in place and also assists in resisting impact and pressure on the cutting part.

When the tooth 1 is used to cut sandstone or any other comparatively soft stone having a high degree of tooth abrading action when cut, the lugs I3' and I4 and the body II are formed of hard, wear resistant metal, such, Vfor example, as lany of the austenitic work hardening stainless steels. When the tooth is used to cut harder 6 stone having a less abrading action, such, for example, as marble, the lugs and body of the tooth are formed of a less hard metal, such, for example, as SAE 1020 cold rolled steel. When the tooth is Aused to cut an extremely hard stone having a still less degree of abrading action. such, for example, as granite, the lugs and body of the tooth arel formed of a still softer meta-l, such, for example, as -5-5-5 red bronze. it is contemplated that depending upon the type of stone to be -cut thelugs and body will be formed of a metal having substantially the same rate of Wear as the crushed or fragmented diamonds lin the cutting part I 2. This results in the lugs and cutting part wearing Luniformly when cutting stone of a particular type.

The herein described diamond type saw tooth, due to the fact that it includes the lugs I3 and I4, has extremely long life and is essentially smooth and quiet in operation. It is capableof being produced at a comparatively low cost and, due to its specific design and construction, is not likely to have its cutting part dislodged from its body.

Whereas the tooth has been described as being used in connection with a saw for cutting stone it is to be understood that the saw that utilizes the tooth may be used to cut any other material. It 4is also to be understood that the invention 'is not to be restricted to the details set forth since these may be modiiied within the scope of the appended claims without departing from the spirit and scope of the invention.

Having thus described the invention what we claim as new and desire to secure by Letters Patent is:

l. As a part of a rotary saw of the type that is adapted to cut stone and embodies a comparatively large flat sided disc-like blade with Va substantially rectangular radially extending notch rin its outer margin,- a, tooth comprising Aa substantially iiat metallic body of no greater thickness than the blade, shaped 'conformably to, and iitting within the notch,arranged so that it is f transversely centered with respect to the sides of the blade, having the outer end surface thereof terminating directly adjacent the outer edge of said blade, and having connected to its leading outer corner or edge portion an outwardly `extending exposed comparatively short metallic lug which denes with said outer end surface of the body an elongated open `top and open sided seat directly outwards of the outer edge of the vblade and which is of less dimension from Vfront to back than the seat is long, and an elongated completely solid block-like cutting part consisting of a metallic matrix and crushed or fragmented diamond particles distributed uniformly throughout the entire matrix, fitting in and extending lengthwise of the seat .and having the inner portion thereof fitting against and bonded directly to said outer end surface of the body and its iront end abutting against the back of the lug, said cutting part being .of greater height than the seat is deep in order that its outer portion projects outwards of the outer end of the lug and exposes diamond particles 'for cutting purposes and being of greater thickness than the lug and the body and arranged so that its side portions project outwards of the sides of said lug and body and expose diamond particles for cutting purposes, said lug being adapted during operation of the saw to absorb shock resulting from contact with the work and tending to dislodge the cut ting part from its seat and also to form a barrier for protecting the front end of said cutting part from being undercut and rapidly worn away by sludge.

2. As a part of a rotary saw of the type that is adapted to cut stone and embodies a comparatively large flat sided disc-like blade with a substantially rectangular radially extending notch in its outer margin; a tooth comprising a substantially flat metallic body of the same thickness as the blade, shaped conformably to and tting within the notch, arrange so that its sides are iiush with the sides of the blade, having the outer end surface thereof terminating directly adjacent the outer edge of the blade, and provided at its outer corner or edge portions with a pair of laterally spaced outwardly extending exposed comparatively short integral metallic lugs which dene with said outer end surface of the body an elongated open top and open sided socket-like seat outwards of the outer edge of the blade and which are each of less dimension from front to back than the seat is long, and a single elongated completely solid block-like cutting part consisting of a sintered metal matrix and crushed or fragmented diamond -particles distributed uniformly throughout the entire matrix, tting in and extending lengthwise of the seat, and having the bottom portion thereof fitting against and bonded directly to, said outer end surface of the body and its ends iitting against and bonded directly to the inner opposed surfaces of the lugs, said cutting part being of greater height than the seat is deep in order that its outer portion projects outwards of the outer ends of the lugs and exposes diamond particles for cutting purposes and being of greater thickness than the lugs and the body and arranged so that its side portions project outwards of the sides of said lugs and expose diamond particles for cutting purposes, the leading or foremost lug being adapted and designed during operation of the saw to absorb shock resulting from engagement with the work and tending to dislodge the cutting part from its seat and also to form a barrier for protecting the front end of said cutting part from being undercut and rapidly worn away by sludge.

3. As a part of a rotary saw of the type that is adapted to cut stone and embodies a comparatively large at sided disc-like blade with a substantially rectangular radially extendingnotch in its outer margin; a tooth comprising a substantially flat metallic body of nogreater thickness than the blade, shaped conformably to and iitting within the notch, arranged so that it is transversely centered with respect to the sides of the blade, having the outer end surface thereof terminating directly adjacent the outer edge of the blade, and provided at its front outer corner or edge portion with an integral outwardly extending comparatively short metallic lug which denes with said outer end surface of the body an elongated open top and open sided seat outwards of the outer edge of the blade, is of less dimension from front to back than it is high and the seat is long and has the sides thereof flush with the sides of the body, and a single elongated solid block-like cutting part consisting of a metallic matrix and crushed or fragmented diamond particles distributed uniformly throughout the entire matrix, iitting in and exthan the seat is deep in order that its outer portion projects outwards of the outer end of the lug and exposes diamond particles for cutting purposes, being of greater thickness than the lug and the body and arranged so that its side portions project outwards of the sides of said lug and body and expose diamond particles for cutting purposes, and having front end extensions in lapped and bonded relation with the sides of the lug, said lug being adapted and designed during -operation of the saw to absorb shock tending to dislodge the cutting part from its seat and also to form a barrier for protecting said front end of the cutting part from being undercut and rapidly worn away by sludge.

4. As a part of a rotary saw of the type that is adapted to cut stone of particular hardness and embodies a comparatively large nat sided disc-like blade with a substantially rectangular radially extending notch in its outer margin; a tooth comprising a substantially flat metallic body of no greater thickness than the blade, shaped conformably to and tting within the notch, arranged so that it is in transversely centered relation with respect to the sides of the blade, having the outer end surface thereof terminating directly adjacent the outer edge of the blade, and provided at its leading outer corner or edge portion with an outwardly extending comparatively short metallic lug which deiines with said outer end surface of the body an elongated open top and open sided seat outwards of the outer edge of the blade and which is of less dimension from front to back than the seat is long, and an elongated solid block-like cutting part consisting of a metallic matrix and crushed or fragmented diamond particles distributed uniformly throughout the entire matrix, fitting in and extending lengthwise of the seat, having the inner portion thereof iitting against and bonded directly to said outer end surface of the body and its front end tting firmly against the back of the lug, said cutting part being of greater height than the seat is deep in order that its outer portion projects outwards of the outer end of the lug and exposes diamond particles for cutting purposes and being of greater thickness than the lug and body and arranged so that its side portions project outwards of the sides of said lug and body and expose diamond particles for cutting purposes, said lug being adapted during operation of the saw to absorb shock resulting from engagement with the work and tending to dislodge the cutting part from its seat and also to form a barrier for protecting the front end of said cutting part from being undercut and rapidly worn away by sludge, the metal of which the lug is formed being of such character that the lug, in connection with cutting of the stone by the saw, has substantially the same rate of wear as the diamonds of said cutting part.

5. As a part of a rotary saw of the type that is adapted to cut stone and embodies a comparatively large fiat sided disc-like blade with a substantially rectangular radially extending notch in its outer margin; a tooth comprising a substantially flat metallic body of the same thickness as the blade, shaped conformably to and tting within the notch, arranged so that its sides are flush with the sides of the blades, having the outer end surface thereof terminating directly adjacent the outer edge of the blade, and provided at its outer corner or edge portions with a pair of laterally spaced outwardly extending integral metallic lugs which denne with said outer end surface of the body an elongated open top and open sided socket-like seat outwards of the outer edge of the blade, are of less height than the seat is long andr have the sides thereof flush with the sides of the body, and an elongated solid block-like cutting part consisting of a sintered metal matrix and crushed or fragmented diamond particles distributed uniformly throughout the entire matrix, tting in and extending lengthwise of the seat, having the bottom portion thereof tting against and bonded to said outer end surface of the body and its ends tting against and bonded to the inner surface of the lugs, said cutting part being of greater heightA than the seat is deep in order that its outer portion projects outwards of the outer ends of the lugs and exposes diamond particles for cutting purposes, being of greater thickness than the lugs and the body and arranged so that its side portions project outwards of the sides of said lugs and body and expose diamond particles for cutting purposes, and having said side portions provided with end extensions in lapped and bonded relation with the sides of the lugs, the foremost or leading lug being adapted and designed during operation of the saw to absorb shock tending to dislodge the cutting part from its seat and also to form a barrier for protecting the front end of said cutting part from being undercut and rapidly worn away by sludge.

VNCENT J. FANTOZZI.

LEOPOLD H. METZGER.

REFERENCES CITED The following references are of record in the flle of this patent:

UNITED STATES PATENTS Number Name Date 1,939,991 Krusell Dec. 19, 1933 FOREIGN PATENTS Number Country Date 326,771 France June 5, 1903 15,593 Great Britain July 29, A1905 105,376 Great Britain Apr. 10, 1917 542,054 Great Britain Dec. 23, 1941 

